In the related art, a resin molded product using an injection molding is known. The resin molded product is used in various fields, and, for example, adopted as a component such as a transparent cover or a lens of a vehicle lamp. Further, with respect to such component, a thinning is required from a viewpoint of weight lightening or material cost reduction.
However, when a thinned component is produced by injection molding, since the cooling rate of the thinned component is higher than that of a thick component, it is necessary to fill a mold with a resin material at a high speed. Therefore, depending on the inner surface shape of the mold, the resin filled at a high speed may not follow the unevenness of the inner surface of the mold, so that a portion that is not filled with the resin may be formed in an uneven portion.
In the unfilled portion, the moisture or volatile components contained in the air and the molten resin exists in a gas state, and as the injection of the resin proceeds, the unfilled portion is compressed and the gas escapes out of the mold along a molding surface. Then, the traces of the gas escaping the mold appear on a surface of the molded product as silver streaks (silver stripe streak), so that the appearance may be deteriorated.
Therefore, in order to suppress the occurrence of such streaks, a front surface cover has been devised in which a gate mark is provided on a surface side of a part of the translucent front surface cover, and a continuous surface on which a knurled unevenness is not formed is provided at a position on a rear surface side facing the gate mark (see, for example, Japanese Patent Laid-Open No. 2017-052105).